Ultraviolet light curable compositions for application to porous substrates based on unsaturated polyesters reacted with amino alcohols

Abstract

Disclosed is a curable filler composition which resists absorption into a porous substrate, particularly one derived from wood, comprising: (1) a liquid, ungelled binder of an unsaturated polyester resin having number average molecular weight of from 500 to 3,000 derived from an ethylenically unsaturated carboxylic acid or anhydride thereof, the unsaturated polyester resin having been reacted with a hydroxyl-containing amine selected from the group consisting of an alkanol amine having a secondary amino group, an alkanol amine having a primary amino group and a mixture thereof, (2) one or more ethylenically unsaturated compounds different from and cocurable with the unsaturated polyester resin, (3) pigment, (4) a free radical initiator, and (5) optionally a carrier solvent for the filler composition. Disclosed is a method of minimizing absorption of a filler composition into a warm or hot porous substrate. Also disclosed is a porous substrate, particularly one derived from wood, having adhered to a surface thereof the cured filler composition.

What is claimed is: 
     
       1. A porous substrate derived from wood having adhered to a surface of said substrate, but not substantially penetrating said substrate, an ultraviolet light cured filler composition produced from (1) a liquid, ungelled binder of an unsaturated polyester resin having a number average molecular weight of from 500 to 3,000 derived from an ethylenically unsaturated dicarboxylic acid or anhydride thereof and an organic diol in a molar ratio of diol to acid of from about 1.10/1.00 to about 1.20/1.00, said unsaturated polyester resin having been reacted with a hydroxyl-containing amine selected from the group consisting of an alkanol amine having a secondary amino group, an alkanol amine having a primary amino group and a mixture thereof, (2) one or more ethylenically unsaturated compounds different from and curable with said unsaturated polyester resin, (3) an ultraviolet light transparent pigment, (4) a free radical initiator selected from the group consisting of a photoinitiator, a photosensitizer and a mixture thereof, and (5) optionally a carrier solvent for said filler composition. 
     
     
       2. The porous substrate of claim 1 wherein said hydroxyl-containing amine is an alkanol amine having a secondary amino group. 
     
     
       3. The porous substrate of claim 1 wherein said dicarboxylic acid or anhydride is selected from the group consisting of maleic acid, maleic anhydride, fumaric acid, itaconic acid and a mixture thereof, and said hydroxyl-containing amine is an alkanol amine having a secondary amino group. 
     
     
       4. A method of minimizing absorption of a filler composition into a porous substrate comprising: (A) applying to a surface of said porous substrate having a surface temperature of from about 38 to about 88 degrees Celsius, a curable filler composition comprising (1) a liquid, ungelled binder of an unsaturated polyester resin having a number average molecular weight of from 500 to 3,000 derived from an ethylenically unsaturated carboxylic acid or anhydride thereof having an acid functionality of at least two and an organic polyol, said unsaturated polyester resin having been reacted with a hydroxyl-containing amine selected from the group consisting of an alkanol amine having a secondary amino group, an alkanol amine having a primary amino group and a mixture thereof, (2) one or more ethylenically unsaturated compounds different from and cocurable with said unsaturated polyester resin, (3) a pigment, (4) a free radical initiator, and (5) optionally a carrier solvent for said filler composition; and   (B) curing said filler composition on said surface.   
     
     
       5. The method of claim 4 wherein said curing is by exposure to ultraviolet light; said free radical initiator consists of a photocuring promoter selected from the group consisting of a photoinitiator, a photosensitizer and a mixture thereof; and said pigment is an ultraviolet light transparent pigment. 
     
     
       6. The method of claim 5 wherein said substrate is derived from wood. 
     
     
       7. The method of claim 5 wherein said unsaturated polyester resin is substantially linear and said ethylenically unsaturated carboxylic acid or anhydride thereof is a dicarboxylic acid or anhydride and said organic polyol is a diol. 
     
     
       8. The method of claim 7 wherein said hydroxyl-containing amine is an alkanol amine having a secondary amino group. 
     
     
       9. The method of claim 7 wherein said unsaturated polyester resin is prepared from said dicarboxylic acid or anhydride and said diol in a molar ratio of diol to acid of from about 1.10/1.00 to about 1.20/1.00. 
     
     
       10. The method of claim 9 wherein said dicarboxylic acid or anhydride is selected from the group consisting of maleic acid, maleic anhydride, fumaric acid, itaconic acid and a mixture thereof; and said hydroxyl-containing amine is an alkanol amine having a secondary amino group. 
     
     
       11. An ultraviolet light curable filler composition which resists absorption into a porous substrate, comprising: (1) from 30 percent to 55 percent by weight of a liquid, ungelled binder of an unsaturated polyester resin having a number average molecular weight of from 500 to 3,000 derived from an ethylenically unsaturated dicarboxylic acid or anhydride thereof and an organic diol in a molar ratio of diol to acid of from about 1.10/1.00 to about 1.20/1.00, said unsaturated polyester resin having been reacted with a hydroxyl-containing amine selected from the group consisting of an alkanol amine having a secondary amino group, an alkanol amine having a primary amino group and a mixture thereof,   (2) from 50 percent to 10 percent by weight of one or more ethylenically unsaturated compounds different from and cocurable with said unsaturated polyester resin,   (3) from 20 percent to 60 percent by weight of an ultraviolet light transparent pigment.   (4) at least 0.33 percent by weight of a free radical initiator selected from the group consisting of a photoinitiator, a photosensitizer and a mixture thereof, and   (5) from 0 percent to 10 percent by weight of a carrier solvent for said filler composition.   
     
     
       12. The composition of claim 11 wherein said dicarboxylic acid or anhydride is selected from the group consisting of maleic acid, maleic anhydride, fumaric acid, itaconic acid and a mixture thereof. 
     
     
       13. The composition of claim 12 wherein said hydroxyl-containing amine is an alkanol amine having a secondary amino group.